1. Field of the Invention
This invention relates to mounting fragile opto-electric modules.
2. Discussion of the Related Art
In asynchronous transfer mode-passive optical networks (ATM-PONs), optical server units (OSUs) and optical node units (ONUs) use transceiver modules. The transceiver modules interconvert optical and electrical signals to support bi-directional, full-duplex communications over an optical fiber. Each transceiver module houses a laser diode for transmitting, a pin diode for receiving, a monitoring diode, and an optical filter for separating transmitted and received data messages.
Connecting a transceiver module to a circuit board of an OSU or ONU is complicated, because the module has glass bead packings that electrically insulate the module""s electrical leads. The glass bead packings are easily damaged if the module""s electrical leads are excessively bent or twisted during mounting of the module. Damage to the packings eventually damages the internal laser diode and/or monitoring diode and degrades performance of the transceiver module. To avoid such damage, transceiver modules need to be skillfully mounted on circuit boards in a manner that reduces risks of applying above-threshold stresses to the packings.
The transceiver modules used by OSUs and ONUs are examples of opto-electric converter modules. Herein, an opto-electric converter module is an encapsulated structure with a rigid housing, i.e., a metal housing, on which electrical and optical interfaces are located. The opto-electric converter module receives a signal of one type, i.e., electrical or optical, from an input interface and transmits a signal of another type, i.e., optical or electrical, at an output interface. Different opto-electric converter modules function as optical receivers, transmitters, or transceivers.
In one aspect, the invention features a process for mounting an opto-electric module. The process includes rigidly fixing the opto-electric converter module to a holder and electrically connecting the module to a connection structure that is configured to slidably receive electrical leads of the module. The process also includes rigidly fixing the holder to a circuit board and then, electrically connecting the connection structure to the circuit board. The holder and connection structure are configured to limit bending stresses on the electrical leads during the acts of fixing the holder and electrically connecting the connection structure, respectively.
In another aspect, the invention features an opto-electric apparatus. The apparatus includes a circuit board, an opto-electric converter module with a plurality of electrical leads, a holder rigidly holding the opto-electric converter module, and a connection structure. The holder is rigidly fixed to the circuit board and the connection structure is rigidly connected to the holder. The leads of the module protrude into holes in the connection structure. The structure electrically connects the circuit board to the electrical leads.